Secrets of Sex (1969)

Starts with this hot brunette with tattoos on her arm and back getting eaten out by some dude on a bed. She’s got that slim, toned body and long wavy hair—looks like she’s really into it, moaning and grinding on his face. Then there’s this other scene where a bald, muscular guy is fucking her doggy style on a couch, and you can see her tattoos moving with every thrust. Later, it switches to a group thing with Cathy Howard, Nicola Austine, and Maria Frost—all three girls are going at it with Mike Briton and this younger guy Elliott Stein. The orgy part is chaotic in the best way: girls making out, guys jerking off, and everyone switching partners. The lighting’s dim but you still get a good look at everything. If you like mixed group scenes with tattooed brunettes and solid fucking, this one’s got it.